您可以通過添加在列表視圖scrolllistener實現和檢查條件，如果列表中最後一個可見的產品最後在ArrayList中，然後調用與增加的頁號的AsyncTask和更新列表視圖，意味着同時在列表視圖和得到後添加視圖從服務器結果從列表視圖中刪除這樣的加載多個視圖 - AndroidListViewLoadMoreActivity.java
public class AndroidListViewLoadMoreActivity extends Activity {
ArrayList<Country> countryList;
MyCustomAdapter dataAdapter = null;
int page = 0;
boolean loadingMore = false;
View loadMoreView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ListView listView = (ListView) findViewById(R.id.listView1);
loadMoreView = ((LayoutInflater)this
.getSystemService(Context.LAYOUT_INFLATER_SERVICE))
.inflate(R.layout.loadmore, null, false);
listView.addFooterView(loadMoreView);
//create an ArrayAdaptar from the String Array
countryList = new ArrayList<Country>();
dataAdapter = new MyCustomAdapter(this,
R.layout.country_info, countryList);
listView.setAdapter(dataAdapter);
//enables filtering for the contents of the given ListView
listView.setTextFilterEnabled(true);
listView.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// When clicked, show a toast with the TextView text
Country country = (Country) parent.getItemAtPosition(position);
Toast.makeText(getApplicationContext(),
country.getCode(), Toast.LENGTH_SHORT).show();
}
});
listView.setOnScrollListener(new OnScrollListener(){
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {}
@Override
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
int lastInScreen = firstVisibleItem + visibleItemCount;
if((lastInScreen == totalItemCount) && !(loadingMore)){
String url = "http://10.0.2.2:8080/CountryWebService" +
"/CountryServlet";
grabURL(url);
}
}
});
String url = "http://example.com";
grabURL(url);
}
public void grabURL(String url) {
Log.v("Android Spinner JSON Data Activity", url);
new GrabURL().execute(url);
}
private class GrabURL extends AsyncTask<String, Void, String> {
private static final int REGISTRATION_TIMEOUT = 3 * 1000;
private static final int WAIT_TIMEOUT = 30 * 1000;
private final HttpClient httpclient = new DefaultHttpClient();
final HttpParams params = httpclient.getParams();
HttpResponse response;
private String content = null;
private boolean error = false;
private ProgressDialog dialog =
new ProgressDialog(AndroidListViewLoadMoreActivity.this);
protected void onPreExecute() {
dialog.setMessage("Getting your data... Please wait...");
dialog.show();
}
protected String doInBackground(String... urls) {
String URL = null;
loadingMore = true;
try {
URL = urls[0];
HttpConnectionParams.setConnectionTimeout(params, REGISTRATION_TIMEOUT);
HttpConnectionParams.setSoTimeout(params, WAIT_TIMEOUT);
ConnManagerParams.setTimeout(params, WAIT_TIMEOUT);
HttpPost httpPost = new HttpPost(URL);
//add name value pair for the country code
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
nameValuePairs.add(new BasicNameValuePair("page",String.valueOf(page)));
httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
response = httpclient.execute(httpPost);
StatusLine statusLine = response.getStatusLine();
if(statusLine.getStatusCode() == HttpStatus.SC_OK){
ByteArrayOutputStream out = new ByteArrayOutputStream();
response.getEntity().writeTo(out);
out.close();
content = out.toString();
} else{
//Closes the connection.
Log.w("HTTP1:",statusLine.getReasonPhrase());
response.getEntity().getContent().close();
throw new IOException(statusLine.getReasonPhrase());
}
} catch (ClientProtocolException e) {
Log.w("HTTP2:",e);
content = e.getMessage();
error = true;
cancel(true);
} catch (IOException e) {
Log.w("HTTP3:",e);
content = e.getMessage();
error = true;
cancel(true);
}catch (Exception e) {
Log.w("HTTP4:",e);
content = e.getMessage();
error = true;
cancel(true);
}
return content;
}
protected void onCancelled() {
dialog.dismiss();
Toast toast = Toast.makeText(AndroidListViewLoadMoreActivity.this,
"Error connecting to Server", Toast.LENGTH_LONG);
toast.setGravity(Gravity.TOP, 25, 400);
toast.show();
}
protected void onPostExecute(String content) {
dialog.dismiss();
Toast toast;
if (error) {
toast = Toast.makeText(AndroidListViewLoadMoreActivity.this,
content, Toast.LENGTH_LONG);
toast.setGravity(Gravity.TOP, 25, 400);
toast.show();
} else {
displayCountryList(content);
}
}
}
private void displayCountryList(String response){
JSONObject responseObj = null;
try {
Gson gson = new Gson();
responseObj = new JSONObject(response);
JSONArray countryListObj = responseObj.getJSONArray("countryList");
//countryList = new ArrayList<Country>();
if(countryListObj.length() == 0){
ListView listView = (ListView) findViewById(R.id.listView1);
listView.removeFooterView(loadMoreView);
}
else {
for (int i=0; i<countryListObj.length(); i++){
//get the country information JSON object
String countryInfo = countryListObj.getJSONObject(i).toString();
//create java object from the JSON object
Country country = gson.fromJson(countryInfo, Country.class);
//add to country array list
countryList.add(country);
dataAdapter.add(country);
}
page++;
dataAdapter.notifyDataSetChanged();
loadingMore = false;
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
讓MyCustomAdapter.java作爲適配器
private class MyCustomAdapter extends ArrayAdapter<Country> {
private ArrayList<Country> countryList;
public MyCustomAdapter(Context context, int textViewResourceId,
ArrayList<Country> countryList) {
super(context, textViewResourceId, countryList);
this.countryList = new ArrayList<Country>();
this.countryList.addAll(countryList);
}
private class ViewHolder {
TextView code;
TextView name;
TextView continent;
TextView region;
}
public void add(Country country){
Log.v("AddView", country.getCode());
this.countryList.add(country);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
Log.v("ConvertView", String.valueOf(position));
if (convertView == null) {
LayoutInflater vi = (LayoutInflater)getSystemService(
Context.LAYOUT_INFLATER_SERVICE);
convertView = vi.inflate(R.layout.country_info, null);
holder = new ViewHolder();
holder.code = (TextView) convertView.findViewById(R.id.code);
holder.name = (TextView) convertView.findViewById(R.id.name);
holder.continent = (TextView) convertView.findViewById(R.id.continent);
holder.region = (TextView) convertView.findViewById(R.id.region);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
Country country = this.countryList.get(position);
holder.code.setText(country.getCode());
holder.name.setText(country.getName());
holder.continent.setText(country.getContinent());
holder.region.setText(country.getRegion());
return convertView;
}
}
}
創建Country.Java爲POJO -
public class Country {
String code = null;
String name = null;
String continent = null;
String region = null;
Double lifeExpectancy = null;
Double gnp = null;
Double surfaceArea = null;
int population = 0;
public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getContinent() {
return continent;
}
public void setContinent(String continent) {
this.continent = continent;
}
public String getRegion() {
return region;
}
public void setRegion(String region) {
this.region = region;
}
public Double getLifeExpectancy() {
return lifeExpectancy;
}
public void setLifeExpectancy(Double lifeExpectancy) {
this.lifeExpectancy = lifeExpectancy;
}
public Double getGnp() {
return gnp;
}
public void setGnp(Double gnp) {
this.gnp = gnp;
}
public Double getSurfaceArea() {
return surfaceArea;
}
public void setSurfaceArea(Double surfaceArea) {
this.surfaceArea = surfaceArea;
}
public int getPopulation() {
return population;
}
public void setPopulation(int population) {
this.population = population;
}
}
爲主要佈局
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent" android:layout_height="fill_parent"
android:orientation="vertical">
<TextView android:layout_width="fill_parent"
android:layout_height="wrap_content" android:padding="10dp"
android:text="@string/some_text" android:textSize="20sp" />
<ListView android:id="@+id/listView1" android:layout_width="fill_parent"
android:layout_height="fill_parent" />
</LinearLayout>
創建main.xml中創建country_info.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="6dip" >
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:text="Code: "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/textView1"
android:layout_below="@+id/textView1"
android:text="Name: "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="@+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/textView2"
android:layout_below="@+id/textView2"
android:text="Continent: "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="@+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/textView3"
android:layout_below="@+id/textView3"
android:text="Region: "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="@+id/continent"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/textView3"
android:layout_alignBottom="@+id/textView3"
android:layout_toRightOf="@+id/textView3"
android:text="TextView" />
<TextView
android:id="@+id/region"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/textView4"
android:layout_alignBottom="@+id/textView4"
android:layout_alignLeft="@+id/continent"
android:text="TextView" />
<TextView
android:id="@+id/name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/textView3"
android:layout_toRightOf="@+id/textView3"
android:text="TextView" />
<TextView
android:id="@+id/code"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/textView2"
android:layout_alignLeft="@+id/name"
android:text="TextView" />
</RelativeLayout>
頁腳查看文本 - loadmore。 xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:gravity="center_horizontal"
android:padding="3dp"
android:layout_height="fill_parent">
<TextView
android:id="@id/android:empty"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:gravity="center"
android:padding="5dp"
android:text="Loading more data..."/>
</LinearLayout>
不要忘記提及互聯網與權限 -
<uses-permission android:name="android.permission.INTERNET" />
你能說清楚你想做什麼嗎？我猜你想要實現一個'OnScrollListener'，它將啓動你的'AsyncTask'來獲取更多的文檔，當用戶到達頁面底部時，更正？這些新文檔將被追加到你的'ListView'的底部嗎？ –
@MarkCramer是的，我想在用戶到底時添加這些項目（下一頁）。 – dinomuharemagic
你應該看看'RecyclerView'。谷歌的'RecyclerView'無盡的名單，或者什麼的。 這裏有一個熱門：http://android-pratap.blogspot.ro/2015/01/endless-recyclerview-onscrolllistener.html 並且在你的滾輪裏面有一個計數器，所以每次你打到結果的結尾時，你增加你的櫃檯...所以你知道你在哪個頁面上。 – nightfixed